1. Field of the Invention
The present invention relates to a method for restoring subscriber-related information in a first database system of a first communication network if the corresponding subscribers are registered as subscribers both in the first communication network and in a second communication network, wherein a second database system for storing subscriber data records containing subscriber-related information is provided in the second communication network and there is a possibility that information dependent on the current location of the subscriber or terminal has to be restored. Such subscriber-related or terminal-related information can be, for example, information on the current availability of a subscriber or terminal, or current terminal-specific facility settings.
2. Description of the Prior Art
In the book by M. Mouly, M. B. Pautet, xe2x80x9cThe GSM System for Mobile Communicationsxe2x80x9d, 1992, F-91120 Paliseau, the updating of the database of the location of terminals in a mobile radio network and the restoration of subscriber-related or terminal-related information within a database after an incident is described especially on pages 470 to 473. In this case, only information on the availability of a subscriber or terminal within the mobile radio network is stored and, respectively, restored. In the method for restoring information on the location of a terminal within the mobile radio network as described here, the unsafe, or potentially wrong, information is marked as such in a first step. Then, other units of the mobile radio network are informed of the unsafe state of this information whereupon these units, too, mark the corresponding information as unsafe. To provide as little load as possible on the signaling load of the communication network, the unsafe data is restored or corrected only if an event related to the subscriber or the terminal occurs such as, for example, a radio contact initialized by the terminal. To ensure such a radio contact within a certain period of time, the information on the location of the subscriber or, respectively, the terminal is updated periodically; for example, once a day. The known method, which is only used within a mobile radio network, presupposes that a unit which can provide, for example, information on the current location of a terminal, receives a message that the corresponding data may not be correct because of a fault case. If there is such a message, this data is updated or corrected, if a certain action with respect to the terminal occurs. To ensure sure such an action within a certain period of time, it is known to initiate a periodic radio contact.
It is therefore an object of the present invention to provide a method for restoring subscriber-related or terminal-related information after a fault in a database system of a first communication network for storing such information for the case where a subscriber or terminal can be reached both via the first communication network and via a further communication network, wherein there is a possibility that information dependent on the current location of the subscriber or terminal has to be restored.
This object is achieved by a method of the present invention wherein, to restore subscriber-related information in a first database system of a first communication network the case where the corresponding subscribers are registered as subscribers both in the first communication network and in a second communication network, a second database system for storing subscriber data records containing subscriber-related information is provided in the second communication network, and a controller for storing in a storage device the subscriber-related information relevant to the first database system from the subscriber data records of the databases of a number of cordless communication systems and for transferring subscriber-related information requested by the first database system to the first communication network is provided in the second communication network. Control of the first database system determines potentially faulty subscriber-related information in the first database system and transfers a request message for requesting the corresponding correct information to the controller of the second communication network.
An embodiment of the method of the present invention provides that the individual cordless communication systems in each case transfer an updating message to the controller if the availability of a terminal allocated to a subscriber via this cordless communication system changes.
The first communication network can be a public communication network having a number of cordless communication systems and the second communication network can be a private communication network having a number of cordless communication systems. The terminals which can be wirelessly connected are, in this case, cordless terminals. More specifically first communication network can be, for example, a mobile radio network. In this case, the terminals which can be wirelessly connected also can be dual-mode terminals having a cordless communication part and a mobile radio communication part.
In an embodiment of the method of the present, the controller stores in matrix form the subscriber-related information relevant to the first database system.
Additional features and advantages of the present invention are described in, and will be apparent from, the Detailed Description of the Preferred Embodiments and the Drawings.